In Windows XP, open the System applet in Control Panel
Click on the Advanced tab, and click Settings under Startup and Recovery.

1. Select the default operating system from the drop-down list in the System Startup section
2. Change the delay time in the field next to ‘Time to display list of operating systems’.
3. Select Edit under System Startup to open the boot.ini configuration file in the Notepad text editor
4. Modify the default text label (i double quotes) for each operating system in the menu.

Windows Vista’s boot menu options are nearly the same to those in Windows XP (click the Advanced system settings link in Control Panel’s System applet, and then choose the Advanced tab).